Harry Potter: Your New Defence Against the Dark Arts Teacher
by Ecthel1on3
Summary: After some years working at the Ministry, Harry decides to have a sabbatical year teaching full time at Hogwarts. These three short stories take us to three different moments of that year: Harry's first lesson to the first years; a more emotional moment teaching fifth years about werewolves; and a final moment with Neville at the end of the year.
1. Chapter 1 - First Lesson

Year 1, DADA lesson:

The students were all excited as their famous teacher walks to the front of the class. Whispers of anticipation grew louder:

"I can't believe we're going to be taught by Harry Potter... THE Harry Potter, can you believe it?" - said a raven-haired Hufflepuff boy.

"I know. My uncle Ernie told me Professor Potter taught him how to duel, and he was on Dumbledore's Army and fought in the Battle of Hogwarts alongside him" - responded a small girl with rounded and excited eyes.

Harry Potter reached the front of the class and, smiling, waited for the students to calm down. He looked delighted to be there. Most students eyes darted immediately to his forehead looking for the famous lightning bolt scar that they all have seen in the Chocolate Frog Cards, on the cover of famous books and biographies, and countless articles of The Daily Prophet about his life, the defeat of the Dark Lord Voldemort and the countless dark wizards apprehensions he had achieved on his career as an Auror.

But it is one thing to look at images of our idols, and an altogether issue to be face to face with him. Some of the students were still with their mouths slightly open in disbelief that the most famous wizard of their time was about to start teaching them how to defend themselves from the most wicked and evil spells wizard kind invented.

Harry Potter looked at his students and was suddenly reminded of a conversation he had in this same castle some 20 years earlier

"I'm talking about you teaching us Defence Against the Dark Arts" – said Hermione

"But I'm not a teacher…" – he countered

A lifetime had passed since the first lessons of the DA. Harry was still not sure if he was a teacher. It was time to found out.

"Welcome to your first Defence Against the Dark Arts at Hogwarts." – he said smiling at his students.

"I remember being in your place. Wondering what cool spells I would learn, or what dark creatures would we study. But the dark arts are more than spells, curses and nightmarish creatures. To defend yourselves, you need to understand that books alone won't help you. You need to train. To learn to be vigilant. To understand and control your fears, knowing that a mistake can cost your life. That's why I'm here for. To teach you how you can identify dark magic, and how you can protect yourselves from it."

The students were silenced. They drank every word he said with rapt attention and were eager to hear more from him.

"I've always been more adept of practical lessons than of lectures. But, my adventures, to give them a more pompous name, also taught me that understanding the principles of a spell will save a lot of trouble in learning it. So, if you please can turn to page 35 of your book, we can start to understand more about our subject of today's' lesson…"

A quick shuffle of book pages filled the room as the students tried to be the first to reach page 35.

"Expelliarmus?" – cried the raven headed boy – "That's a basic spell. I've already learned it. My cousin taught me last summer"

Harry smiled.

"A basic spell that can save your life. It saved mine. Twice. Against Voldemort"

The boy didn't seem too impressed or even to believe Harry.

"Expelliarmus!"

The book flew out of the boy's hands as it was struck by a jet of red light out of Harry's quickly drawn wand. With the skill of the seeker he once was, Harry caught the book in mid-air and put it back on the desk of his awestricken student.

Harry proceeded as if nothing of extraordinary happened.

"Expelliarmus is a defensive charm, used to disarm your opponent…"


	2. Chapter 2 - Concerning Werewolves

Year 5, DADA lesson

"... Can anyone tell me how can we distinguish a werewolf from a normal wolf?" - Harry asked is class, as arms stretched in the air. "Mr Norris?"

A tall dark boy got up and recited:

"A werewolf can be distinguished of a common wolf by its shorter snout, tufted tail and smaller pupils. Werewolves are also more aggressive and, contrary to the common wolves, tend to seek and attack humans" - he finished.

"Very well, Mr Norris. Ten points to Slytherin"

The boy's desk mate clapped his back in approval, while at the front a red-headed girl rolled her eyes in contempt at his smug smile.

"As you are all aware, there is no known cure for lycanthropy. Once a human is bitten by a werewolf, he becomes infected and will turn into a werewolf herself at each full moon. There are however ways to ease the suffering for the person infected and to reduce the risk of an attack. Can anyone guess..."

The red-headed girl almost knocked her chair as she stood up to answer

"The Wolfsbane potion helps a person control its transformation and to remain tamed during the phase she turns into a werewolf" - she said in a single breath as if afraid someone might be too fast and answer before her.

"That is correct. Take five points for Gryffindor"

"Only five?" - she said annoyed. "Norris got ten."

At the end of the class, Norris' Slytherin friends grinned widely, but he blushed slightly and looked at his desk.

"Well..." said Harry with a little discomfort - "Mr Norris gave a full answer, while yours is correct but does not list all the measures that we can employ to try and ensure that a werewolf remains tamed, and does not represent a treat to himself and to others."

He directed the students' attention to an image of a wolf quietly resting alongside a cat.

"Here you can see a werewolf in the company of other animals. Werewolves are only a danger to humans, and not to other beasts, whom they can tolerate and even play with. There are been known cases of werewolves being soothed by the presence of other animals, or in the presence of Animagi, that can keep them company."

The girl frowned her face and narrowed her eyes towards Harry, seeming resented that he corrected her.

Harry noticed it but decided to let it slip and continue his lecture.

"However the Wolfsbane potion remains the best option for safety and to ensure a less painful transformation for those infected. Unfortunately, due to its complexity, it's not something that is easily available to all werewolves. The Werewolf Care Act of 2013 launched a pilot experiment by the Ministry of Magic of creating a new registry of werewolves in Britain, ensuring that all of those that registered received a Ministry approved and quality ensured batch of Wolfsbane potion each month." - he continued passing around the class drawing the gaze of his students.

"This reform allowed several infected wizards and witches to come out of hiding and regain the ability to have a normal life, taking into account the obvious medical situation they have to endure. But the stigma against werewolves still runs deep in our society and there are those that still prefer to remain in hiding, shunned from society."

"Excuse me Sir" - a small girl with big brown eyes interrupted - "isn't that dangerous? Shouldn't the Ministry ensure that werewolves are caught and... well, I mean, they are dangerous. They are evil."

"Werewolves can, in fact, be dangerous. But evil is a strong word..."

"They kill people" - the girl blurted out.

"Let us look at this from another angle. Would you say that dragons or hippogriffs are dangerous creatures? They can kill or maim a human."

"Yes, they are dangerous creatures. Everyone knows that".

"Of course. But would you call them evil?"

"No. I mean, they're beasts. They don't think like people. They attack to eat or to defend themselves."

"Quite correct. And that's what happens with a werewolf. Once transformed, the wizard or witch, loses its ability to think like a normal person and acts according to the beast's instincts, that are to attack, kill and eat its preys".

Harry noticed that some of the students shifted in their seats. Small movements that distanced them from him or, more precisely, from the point he was trying to make.

"There are werewolves that are evil. Like there are wizards that are evil. But not all werewolves plan the best way to attack new victims. Some of them distance themselves from society in order to protect others from suffering from the same ordeal."

"Did you know any werewolf, Professor?" - asked a small sandy-haired boy at the front of the class.

"Yes. I've met several werewolves throughout my life. Both good and evil. In fact, I met a werewolf for the first time right here at Hogwarts, in this very classroom. He was the best Defence Against the Dark Arts Teacher I've had. He died fighting Voldemort on those grounds outside".

The class went silent. Harry lost himself temporarily looking through the window remembering Lupin's lessons, from Kappas and Boggarts to the amazing obstacle course he devised to test them. A smile crossed his face remembering Hermione's Boggart of Professor McGonagall telling her she failed all her exams, as his eyes become watery.

He composed himself to face his class again.

"Ok. For homework..." - a groan rumbled across the room - "Yes..." he continued - "for homework, I want 2-foot of parchment on the distinctive characteristics of werewolves and the ways the Ministry of Magic tried to deal with the werewolves' population throughout the years. To be delivered after the Christmas Holidays."

The students smiled in relief as they started to pack their bags. The redhead girl, however, stood up and raised her arm

"Sorry, I have a question" - she said bravely.

Harry considered her for a moment.

"And what is your question, Miss Potter?"

Lily looked at her father defiantly:

"When are you going to teach us about Dementors?"

"When are you going to teach us about Dementors, Professor?" - he stressed the last word, without a hint of a reprimand.

"Yes. Sorry, err... Professor. When are we going to study Dementors, sir?"

"We'll be studying Dementors around Easter time" - Harry answered with a smile.

"And are you going to teach us the Patronus charm?" Lily asked enthusiastically - "Sir?" She added quickly.

"Well..." - Harry pondered his response - "The Patronus charm is a very complex bit of magic. One that requires years of training and great magical skill. It's something that is usually taught in the seventh year..."

The students start to protest, but Lily was louder:

"Mom told me that you taught her and the rest of Dumbledore's Army in her fourth year. It's not fair."

"Miss Potter, I taught your mother, as well as others, during a period of great uncertainty and risk, when our lives were in danger. Fortunately, that's not the case today."

Before she protested again, Harry continued.

"However, I believe that this class as shown that it's ready to learn and perform more advanced magic and, as such, in due time, I will teach you the Patronus charm".

The class celebrated excitedly, while Lily smiled at him.

"Now hurry up everyone, or you'll be late to Herbology." He crossed the class to exit it but stopped at the door looking at Lily that was still packing her stuff.

"Oh. And Miss Potter?" - he called - "Five points from Gryffindor for your little insubordination."

Lily stood mouthing a silent protest to the air, not able to voice the injustice of it, while Harry winked at her and left the room.


	3. Chapter 3 - End of Year Reunion

End of Year, OWL exams

The two men were walking down the empty corridors talking quietly. Today marked the end of the exams season, and while everyone was longing for the end of year feast, there was still N.E.W.T. and O.W.L. examinations underway for fifth and seventh-year students. Being the culprit of causing some sort of distraction that could lead a student to lose some points was something neither of them was willing to risk.

"Oh," said Harry suddenly "I forgot to tell you that Teddy and Victoire are joining us for lunch on Sunday. You don't mind, do you?"

"Not at all. I'll tell Hannah" said Neville smiling.

"Thanks." with a sigh of relief "Ginny would jinx me. I've told her two weeks ago I would tell, but it slipped my mind"

"That would be a laugh" suggested Neville. "The Daily Prophet would have a field day with that one. "Top Ministry Official involved in domestic scandal" or "Has Former Chosen One Harry Potter lost his abilities?"

They both laughed a little too heartily and were frowned upon by three elderly witches on a portrait stirring a cauldron under a full moon, or what the artist of portrait thought was a full moon, and was strangely similar to a stilton cheese ball enlarged and slightly crooked.

"I've endured worse from them, and it would be better to be on the news because my wife hexed me than because the wizarding world thinks I'm a brain-addled deranged teenager."

They stopped at the door of Gryffindor's Common Room. None of them had set out for this particular location when they started walking. They've just wandered through the corridors, side by side, steadily drawing near that place as if that was the obvious destination. Harry couldn't remember wanting to go there. He had avoided going there all year. But there he was. And it was his feet, if not his brain, that led him here.

"Have you been inside yet?" Neville asked fully aware of the answer.

"Not really. I've... never found the time with all the classes and keeping up with work at the Ministry" Harry stumbled to justify.

Neville understood. He knew what Harry was feeling. The excitement mingled with anticipation and dread that he had experienced before.

"It's ok. I get it. It took me three years before I gather the courage to go inside."

He let Harry have a moment and then continued:

"Want to go in? If you don't that's fine, we can..."

"No." interrupted Harry "Let's enter".

They stood in front of the Fat Lady portrait while she pretended to be interested in what was happening in some empty landscape portraits on the other side of the hall. She was making an awful job of ignoring them. Harry grinned.

"Hum hum." Neville coughed. "Can we come in?"

"Oh sorry, didn't see you there." said the Fat Lady in a high-pitched surprised voice.

"You're always welcome here Pro-fes-sor Longbottom." she continued stressing Neville´s position while ignoring Harry. "But I'm afraid that the Gryffindor Common Room is under restrict access only to Gryffindor' students and respective Head of House, as is Hogwarts rules. You may enter. But I'm afraid your friend must stay outside." she politely smiled at Harry with a triumphant gleam on her eyes.

"Well... Harry's a Gryffindor, and I'm Head of House, and he's with me, so there's no problem with that" Neville told her politely.

"I'm sorry, but rules are rules. I'm a Hogwarts' portrait, and as so, I'm bound to defend the entrance and secrets of Gryffindor's common room from other houses and strangers". She made a point in saying the last word as if throwing a punch to Harry.

"He's no stranger!" said Neville indignantly. "He's Harry Potter. I doubt there's a more highly regarded Gryffindor than him, aside Godric Gryffindor and Albus Dumbledore"

Harry almost burst out laughing, seeing the game the Fat Lady was playing. She was annoyed at him for not visiting her all year. He decided to play along with her.

"That's ok Neville." he said in a friendly tone "She probably doesn't remember me with all the students she's seen throughout the years. Or maybe Sir Cadogan was right about her after all" he whispered to Neville, in a very loud way so that the Fat Lady could clearly hear what was said.

"And what has that sycophantic buffoon has been saying about me?" she burst out, with her eyes bulging and her nostrils flaring "He´s he telling lies again about my... my little indiscretions with Violet? Because that was ages ago and it wasn't that..."

"Oh no, nothing of the sort." Harry told her "He was just telling us how you're getting old and can't do a proper job because you forget things. Which he says it's natural at your age..." Harry was stopped mid-sentence by the angry retort of the Fat Lady.

"Old? I'm old? He's the one dressed like a walking trash can and calls me old? I'm the one who can't do my job, while he can't event mount that fat pony of his without shoving his face on the ground? And he as the nerve to call me old?" Her face was red with anger. Her hands were curled in fists.

"And you" she burst in Harry's direction "I know perfectly well who you are Mr. Harry Potter, the Boy Who Lived, The Chosen One." Her eyes were now so narrow it was hard to see them. "I remember very well who you are. I remember every time you sneaked at the dead of night to wander the corridors out of hours doing some mischief."

"But apparently" she continued with a tone of sarcasm "famous Mr. Potter is the one who forgot that he's a Gryffindor, and decided he's too important to pay a visit to his old common room and... to me" she crossed her arms, turned her face way sounding hurt.

Harry knew this was the thing that was bothering her. The fact that he didn't visit this place once all year was the reason she was acting like a spoiled child who didn't get what she wanted from her parents.

"Caput Draconis!" Harry said softly. She was taken by surprise and forgot to act as if she was angry with him.

"That was the first password we used on my first year. Of course, I remember. But I'm a teacher now." he explained to her like. He adopted the same tone of voice he used to explain to Lilly that she had to wait a little longer to go to school with her elder brothers. "I can't just go around and enter my old house dormitories. People will say I'm playing favourites. And my daughter is in Gryffindor. It would be awkward for both of us if I just showed up while she was with her friends, or with..." He didn't finish the sentence.

"I understand," she said with a sigh. "Of course, you can't go entering students' dormitories at will unless you're the Head of House. But I was hoping you'd pay me a visit anyway."

"You're right. I should've come sooner. I'm sorry".

And, as Harry knew it would, the apology worked like a charm. The Fat Lady smiled, winked, and revealed the hidden entrance.

"Go on. Enter" she told them

"Thanks," said Harry. But he stood there, looking at the entrance without moving. His shoes felt like they were magically filled with lead, and he couldn't, for all his might, forced them to move. Not that he was really trying. He just stood there remembering all the times he had passed through that door before. They felt like a lifetime away. They were a lifetime away.

"Comme' on," said Neville pushing him slightly. "It's easier if you just do it. The longer you stand there, the harder it will be to force yourself to entry"

He climbed through the door and, after a deep breath, Harry followed.

Harry didn't know what he had expected. He didn't even know if the familiarity of the room was comforting, or slightly distressing. It felt as if the two decades that passed failed to materialize themselves in the old common room. The same armchairs that he and Ron used to wrestle younger students from, were there. As was the mantlepiece where he talked with Sirius. Everything was the same. Yet... there was something not quite right in the room. Something that he couldn't quite grasp what it was. He felt like a stranger there. Like this was not his common room.

That was odd. He spent six years there. Six happy years, for the most of it. This had been his first real home. And it felt as he had just left it a minute ago. Just like he had just come back inside after realizing he forgot his potions book on his way to class. But in the tiny fraction he spent outside of it, the room has changed itself, while, confusing as it sounded, staying the same. Everything thing was in the right places, but the feeling of the room was not one he recognized anymore. Not one he felt comfortable.

But "this is not MY common room" he thought for himself. There's no Ron munching over a chocolate frog, no Hermione's over a stack of books trying to get full marks on another homework, nor Fred and George creating another raucous experience and making everyone laugh...

It was only him and Neville there. But they weren't the same lost kids that were trying to fit in the wizarding world. One to famous without knowing why. The other not sure he was supposed to be there, to begin with. They were two grown men trying to relieve a little bit of that youthful joy, that made them feel as if they were a part of something. They've outgrown the common room. It belonged now to a new generation of Gryffindors that were trying to live their own stories. It has passed on.

"It's weird, isn't it?" Asked Neville.

Harry didn't answer, but his looks told everything.

"It's the same, but not really. If you know what I mean" continued Neville. "It's like we're on the outside looking in."

"Yeah..." Harry muttered, going close to the window and looking to the grounds. An owl passed over the tree line of the Forbidden Forest. Harry could've sworn it was white as snow, but probably just a trick of the light.

"Shall we go then?" Asked Neville. "The exams should be over in 10 minutes, and we want to get to Hagrid's before being bombarded by students anguishing about the answers they gave in question 7 or something of the sort".

Harry half-smiled, nodded and followed Neville through the entrance hole. They silently made their way to the castle's grounds. There was a light breeze from the lake, that softened the heat of the day. Harry saw a large tentacle emerging from the water, and students, free of exams, relaxing by the lake. He was reminded of summer days, much like this one, he spent with Ron and Hermione near the lake ages ago.

The familiar path to Hagrid's hut was now home to a white marble cenotaph shining in the sunlight. Its marble shinned as if it was encrusted with small diamonds that reflected the sunlight as thousands of rainbow beams across the grounds. A trick of the light that was as good as any enchantment in Harry's opinion. The cenotaph was comprised of four perfectly cut blocks of rectangular marble, vertically stacked on top of each other, each slightly smaller than the previous one. These rested above three large horizontal ones, forming three small steps. At the top, there was a white tomb that represented the resting place of the fallen.

In each side of the monument, stood the banners of the four houses, testifying the unity of Hogwarts in mourning. On both tops the crest of Hogwarts was carved within a head of laurels, on top of which the following was written:

Battle of Hogwarts

May 2, 1998

Below the crest, more words were engraved filling almost all of the lower block. The greater block of words read:

Remember

the Dead who fell

so you might

Live in freedom.

These words were followed by a list of about 50 names and dates that Harry knew by heart. He read them nonetheless, lingering more on some names than on others as they stirred some deep-rooted memories:

Collin Creevey 1981 - 1998

Fred Weasley 1978 - 1998

Lavender Brown 1979 - 1998

Nymphadora Tonks 1972 - 1998

Remus Lupin 1960 - 1998

Severus Snape 1960 - 1998

Harry stood there, hands in his pockets, rooted to the floor, eyes fixed on the names in front of him, but his mind gazing into memories that, painful as they might be, still brought comfort and some happiness. He couldn't quite describe the feeling if he was asked. He wasn't sure if it was sorrow mingled with joy or happiness tainted by melancholy.

"Potter! Longbottom!"

Harry froze. The voice had jerked him out of his numbness and made him stand fully alert. Even after all these years, it made him feel like he had done something wrong and was about to be told off. He turned to the doors of the castle and saw Professor McGonagall, slowly walking towards him, supported in a cane, but with the same expression, she wore when he first met her, at his very first day at school. Even using a cane to better move herself, she still seemed like someone you wouldn't want to cross.

He remembered he was a teacher and surely- why, surely - he wasn't about to be told off by his former Head of House. He looked sideways to Neville and was both amused and apprehensive when he saw that his arms were stiff as boards and he was shuffling his feet a little nervously. Professor McGonagall got nearer, and Harry relaxed as he saw a little smile on her eyes.

"Hello Professor" they both said at almost the same time.

"So, Potter, how was your teaching experience?" she asked with a tone of something of amusement in her voice.

"It was... uh... fine, I guess," Harry said, not sure if this was the kind of answer expected by the former Head of Auror Office, current Head of Magical Law Enforcement and guest professor of Defence Against the Dark Arts at Hogwarts School of Witchcraft and Wizardry.

"Fine? You guess?" continued McGonagall, clearly amused by his awkwardness.

"Well..." he continued, still not sure what he was about to say. "it was a challenge. It's different to plan a whole year of lessons than it is to prepare a single lecture. And keeping students interested in the subject and properly behaving, certainly is hard."

"I'm glad you appreciate how hard it is for teachers."

"So, Professor, how did the exams go?" he asked trying to sound calm.

"Fine, I guess" answered McGonagall with a small grin.

Harry smiled back "I was wondering..." he started before being unceremoniously interrupted by his old teacher

"I'm not going to tell you what marks Albus got." She said bluntly. "But" she continued seeing his expression "you need not to worry. He did well. Very well indeed. Just like Ms. Potter did on her OWLs examination this morning".

Harry grinned in relief.

"Thank Merlin they took out for the women's side of the family," McGonagall said.

"What?" said Harry dumbfounded. Neville snorted.

"Potter, you were always a gifted student, but never worked hard enough to meet your potential. Ginny, and your mother, on the other hand, we're not only gifted but hard working. Like your kids. Well, at least these two." she said with a hint of both amusement and annoyance. "Your eldest son clearly his more like you, and even more like your father and your godfather. You did name him right". Harry chuckled.

"I hear he followed his uncle's example and pursued a career as curse breaker. Am I right?" asked McGonagall.

"Yes. They're in Peru right now. Bill thinks that the legend of the Fountain of Eternal Youth means there's a Philosopher's Stone somewhere hidden in the Amazon jungle." Harry explained, not entirely concealing his pride, and a little bit of jealousy, on his eldest son adventure.

"Hum... well, Mr. Weasley always seemed eager to put himself in unnecessary danger even while at school, so that doesn't surprise me". Harry couldn't quite understand how much of her tone was of disapproval and how much was of pride.

"In any case" she continued "I'm glad to see you teaching Potter. I think it was about time you let others chase dark wizards and do your part in educating younger generations." She smiled at him.

"Well, I know I've said several times before, but I really would like to have a quiet life from now on".

"You and me Potter" McGonagall added. "I think that three generations of Potters and Weasleys are more than enough to earn a quiet retirement".

"You won't come back, Professor?" asked Neville slightly alarmed.

"Oh no, Longbottom. This was my last N.E.W.T. examination. I've notified the Ministry six months ago that after this I'm going to retire, for good this time. I'm getting too old for this." the old teacher sounded tired.

"You're not old" blurted Harry. "And no one knows more than you about Transfiguration".

McGonagall smiled gently.

"Your parents would be proud of the man you become." She added with a glint of emotion on her eyes.

"I like to think so". Harry confided in a small voice.

"I know they would. I'm proud of you. Of both of you!" she added looking intently to Neville. "You lot really turned out alright."

The pride in her voice was unmistakable this time, and Harry was reminded of the time she proudly confronted Amycus in Ravenclaw´s tower. Neville looked like he had been smacked in the face by the Whomping Willow.

Professor McGonagall said them farewell and took the path towards the gates and out of Hogwarts for the last time.


End file.
